Conveyer system for assembly lines and the like



|. GALPER April 28, 195.3

CONVEER SYSTEM FOR ASSEMBLY LINES ND THE LIKE Filed Dec. 30, 1950 7 Sheets-Sheet l l. GALPER April 28, 195.3

CONVEYER SYSTEM FOR ASSEMBLY LINES AND THE LIKE Filed Dec. so, 195o '7 sheets-sheet 2 Q Sm L m M WN i H I a f @www T- A. y Si www 2D kN a Qs wmv. a @.@N i

April 28, 1953 l. GALPER 2,636,591

I CONVEYER SYSTEM FOR- ASSEMBLY LINES AND THE LIKE Filed Dec. 50, 1950 7 Sheejs-Sheet 5 April 28, 1953 l. GALPER CONVEYER 'SYSTEM FORSSEMBLY LINES AND THE LIKE Filed Deo. 50.' 1950 7 sheets-sheet 4 111W ya' April 28, 1953 l. GALFER coNvEYER SYSTEM .FOR ASSEMBLY LINES AND THE LIKE 7 SheetS-Shgt 5 Filed Dec. 30, 1950 APll 28, 1953 y lcs ,ALPx-:R 2,636,591

I CONYEYER vs :lysgrlEM FORT-*ASSEMBLY LINES AND THE LIKE Filed neg. so, 195o 'r sheets-sheet e 10 Eig.

l. GALPER April 2s, 195s 'couvm- SYSTEM Fo'R AssEMBLy LINES AND THE LIKE 17 Sheets-Sheet '7 Filed Dec. 30, 1956 @HQE Patented Apr. 28, 1953 UNITED, s,Terri;s Para conversa sYs'ruM--Fon assiiMLYimNEsf. ANDLTHE Llflclilv Isadcra- Geleen; Manches-icuii@ Hf implication December 30, 1950;,SeijialiNm 7.2.03;724;

iifaims-.l (0119.814295 veyors',v on Which'a-ny-of numerous things maybe circulated past stations distributed along the conveyor system therebyl to provide one ormore pools, off; Whatever is being conveyed, from whichv pool or' pools the stationsimaybe sup-plied, withI whatever is beingl conveyed, onpr-inciplesjofautor matic ejection, selection and-rejection, dependingy uponthe requirements at particular stations;

IIfhe invention 'ha-s generalutility in the conveyingfield andwill be found especially advantageousior conveying'worl; units cliparts, or anything; else that may be desired, to the various stations alonganassembly-line, ortho like.' It is herein disclosed in connection with an assem-` bly-line along which Workers at the various stationsperformv particular operationsor duties incidentto they assembly ot work parts which deliver to the work stationsin partitionedx boxes. It should beA understood, however, that the-Work parts; or whatever isl beingconveyed; may be variously.- delivered at thei stations to suit any particular requirements, the boxes of Workt parts'V herein shown being exemplary rather than limit--` inain this respect.

Prior-f conveyor systems ofl types. suitable. fory assembly linesi andthelilre, soli-ar asl'am aware',v-

have oper-atedl on principlesv of predetermined timing and critical balancing of the, operationsA to-V beiperformed at. all of tliek stations) alongA the assembly line.. Heretofore, anyy predetermineds.

timing and'v criticall balancingot such conveyor v systems has been.- greatlyinluenced' by the sluwel est worker or Workers along theline.` @nel ab-AVA normally: slow', Worker might be they means; of delaying the Workers at allsubsequentstations waiting for the outputv of the abnormally slowY worker. Hence, it has-lnotlbeen practicable'i with the prior assembly lineconveyorl systems to emr; ploypiece-work incentives, or to speed` uptheassembly `operations beyond the capabilitiesof tliel slower; Workersv alongl the line;

It'v is among the objects of; my present iin/tenev tion` to. provide a conveyor system, suitable for assembly lines, and the like, which operates on principles which make itunnecessary toprede-- termine and" establish anyy critical balance inthetiming of Work operations at successive stations along` anA assembly line. Accordingr` tothe invention., workers. at theA various stations receive morir from-.continuous circulating pools ofv work,-

f: creasingI the. output,- of'; the indi anat theindividuai;workerslalongfa pool receive worlc automaticallyvfrom thespoolronlyas fast' as; each-,can handlelit with-.theloutput ofl all (litho.y Workers along the pool' delivering to. a station, furtheri along; the, line; or to one or more.013116.11k

pools further; alongf the.t line.

Anothenl 0b.]` ectis-to provide,` a; conveyor system, suitableforassembly lines; anchtheflike, wherein; therworlifcirculatesfm continuous circuitous kPools 1 atisuccessive locations alongithesystem andauto;

matcally delivers to Stations.y distributed; along at tnestations, can handle1 it, whereby itl becomes,- feasib1e ton emplovpeceeworls incentues fon in-f ual Workers- Byftuuslmalutamineac niet supply Oifwi'li fromlwhion individualiwarilsessf areslieclisiiflliilr matically in accordance with their individualL outputs and advancingthe-cumulative output oi" ooi to, stations or .l l each individual fi iiq, as Slew as. licor-She desires @sie ceiiatlecii.: amil the feci that. @ne Worker may worlfN` tast and other, slow, will be z miese@ tile-Qu uleiiYe/utpui'ofall of the at. anu particular rie-0l! Still another object of the inventionis to prol- Vide-a riieiiiod.,A for deliveries iOfWOrlI 'Sietionsalona an assembl linger thelike, Whe robyv Y, i. eerie; chemicus pools of work are arranged and adapted tot'leliver Wer-15.1 Selecteer te distributed along the respective circuitous pools, and ti meals ofi units-0i, work successie c0915'. akelig the assembly linel is mainte aldloy` depositrtl'leref in @incitera massonica iolm Weils stations tributed. alpes ciL were.: u Weils @Gedisa edele i portieri there@ @ed any siiiiableeiimber; Of Cdr1- tinu-ous circuitous conveyors-are arranged in succession along the centrally disposed conveyor` with any suitable numberv` of stations distributed along the irouitous conveyors, one or moreY ci the cireuitous 'conveyorsL being supplied, from the centrally disposed conveyorwitht Whateveri is; be`

,l inge conveyed, and. eaclil of.;y thetcireuitous conveyors providingl al. pool from which a. unit ofvv Whatever is being conveyed; delivers selectively`v tot amt particular stationl only agiterv a previously delivered unit at that Station has beenr remos/edi from. thellgicationto which, iii had; been. delivered.

lplenishes the supplies cf units in at least some of the pools, there being automatically responsive means at stations along each circuitous conveyor whereby a unit delivers from a said pool to any particular station only after a previously delivered unit has been removed from the receiving position at that station, and there being defiector means for directing units from the centrally disposed conveyor to at least one of said stations, and automatically responsive means for delivering units from the centrally disposed conveyor to one or more of the circuitous conveyors.

A still further object of the invention is to provide conveying and delivering apparatus wherein three belt conveyors extend in parallelism along an assembly line with the central conveyor elevated above the other two and with said other two travelling in opposite directions, there being rotatable elements at spaced locations along the conveyors arranged and adapted to carry units of Whatever is being conveyed from one to another of the two oppositely travelling lower conveyors, whereby said units on the lower conveyors travel in circuitous paths between the rotating elements to provide pools of said units from which individual units may deliver to stations along the circuitous paths in response to removal of a previously delivered unit from the receiving position of any particular station.

It is, moreover, my purpose and object generally to improve conveying systems and more especially such systems which are suitable for supplying conveyed items selectively to the stations along an assembly line, or the like.

In the accompanying drawings:

Fig. 1 is a diagrammatic plan view of an assembly line apparatus embodying features of the invention;

Fig. 2 is a fragmentary plan view of one portion of the apparatus of Fig. l, on a larger scale;

Fig. 3 is a cross-sectional view on line 3-3 of Fig. 2;

Fig. 4 is a cross-sectional view on line 4 4 of Fig. 2;

Fig. 5 is a side elevation of the portion of the apparatus shown in Fig. 2;

Fig. e is a top pian view of the left hand end portion of leg A of the apparatus of Fig. l, on the scale of Figs. 2-5, the enclosure for the conveyor pulleys being removed;

Fig. '7 is a view similar to Fig. 6 but showing the right hand end portion of leg A of the apparatus of Fig. 1;

Fig. 8 is a side elevation of the portion of the apparatus shown in Fig. 6; Y

Fig. 9 is a side elevation of the portion of the apparatus shown in Fig. 7;

Fig. 10 is a cross-sectional view on line Ill-l0 of Fig. 1, on a larger scale;

Fig. 11 is a top plan View of leg B of the apparatus of Fig. 1, on a larger scale, and with the central portion of the leg broken away;

Fig. 12 is a side elevation of the portions of the apparatus shown in Fig. 1l;

.Fig. 13 is a top plan view of the right hand end portion of leg A of the apparatus of Fig. 1, on a larger scale;

Fig. 14 is a cross-sectional View on line lli-I4 of Fig. 13;

Fig. 15 is a cross-sectional view on line I5-I5 of Fig. 4 showing in top plan one of the ejector mechanisms for delivering work from the continuous circuitous conveyors to the adjacent work stations;

Fig. 16 is a bottom plan view of the ejector mechanism shown in Fig. l5;

Fig. 17 is a fragmentary top plan view showing one of the transfer mechanisms for transferring work from the central conveyor belt toone of the lower conveyor belts for replenishing the supply of work in a circuitous pool;

Fig. 18 is a side elevation of the portion of the apparatus shown in Fig. 17; and

Fig. 19 is a wiring diagram showing one way of eiecting electrical connections and circuits for operating the illustrated conveyor system.

Referring to the drawings, the apparatus represented in Fig. 1 provides an assembly line of generally U-shape having work stations distributed along only the generally parallel legs A and B of the U. This illustrated apparatus, for illustrative and descriptive purposes, includes six circuitous conveyor pools distributed along the parallel legs A and B but it should be understood that the invention may be embodied in apparatus having but a single circuitous pool or any other desired number of the pools.

In Fig. l, a work table IU extends along the leg A, providing oppositely disposed work stations distributed along the opposite sides of the table. In a similar manner, a work table i2 extends along the leg B, providing oppositely disposed work stations distributed along the opposite sides of table l2.

According to the invention, units of work progress from station i or la, at the left hand end of table iii in Fig. l, to the opposite end of table i@ through the medium of three conveyor belts I4, i6, I8 which are centrally disposed in parallelism between the opposite sides of the table and above the plane of the top of the table. The middle conveyor belt is is elevated somewhat above the level of the belts I4, i8 (Figs. 3 and 4) and constitutes a main conveyor from which units of whatever is being conveyed may be transferred directly to particular stations and to particular circuitous pools as later described herein in greater detail.

Workers at various stations along the table I0, after completing operations on units delivered to those stations, place the units on central conveyor belt i6 for delivery to stations further along the assembly line.

When units of work are being conveyed along the assembly line, the units on central conveyor belt I6 at the right hand end of table lli in Fig. 1 are delivered to the right-angularly related conveyor belt 20 which in turn delivers them to the central elevated conveyor belt 22 which, with conveyor belts 24, 2S, is centrally disposed between the opposite sides of the table i2 and above the plane of the top of table I2. Work units delivered to conveyor belt 22 progress to the left along table l2 and will be removed from the assembly line at station 3l or 31a at the left hand end of the table l2, either manually or otherwise.

The particular U-shaped assembly line illustrated in Fig. 1 is designed to provide an adequate length of assembly line within a building bly line,x of the same len-stili ItslicmldfV beurvnifeii,-A

stood; however,A that thev features of theginvenr tiert may; be: employedv in straight g assembly lines,

Uf-shapedfassembiy lines, and inassembly lines:v

which mayextend;sinuously-back andiforth across theilengthor Widthjot aroom as tunes-.vos maybe; reoty "redto; attain needed; over-all lengtlit` of assembly l' Also, ity should be understood that the. nu eroi Work stations elisir-represented .mplary andwasseieoted'for, conv venience of illustration.. Actuallytbeassembly lino apparatus may inade up oit-sections adapt:- ed-to Abe assembled together to provide. an; assemblyline oi any desired` length andhaving anyl desired number of stationsand ciicuitousgconveyor pools.

Considering iirrtrv the progress ofwork units along.- tne table t8, theconveyorbel-tsl'l, lil extend over suitable pulleys atthe opposite ends of the; tablal the pulleys attire left handend oi table l Fig. l being mounted with-in thehous ing il., and pulleys at the right hand end. of table lllI inj Fig. l being. mounted Within. the housing il. As best seen inFigs. 6 9, vthe housing Hz at the right hand end of table il) houses an electric motor 2li which. supplies the power for drivingthe. conveyor belts is, i8, the upper run of the belts lll, l5 being ritten to theright. in the direction of advance of work along table IIL. While: belt i3 is driven in the opposite direction.Y Any suitable drive connections may bey ein,-y ployed between motor 23 andthe main conveyor pulleys in housing il. Figs. 'Z and 9 show all three of the main pulleys 3S, 32, tl mounted on shaft Pulleys Sli.r and-32 are firedon shaft 36 for rotation. in unison, while pulley tt isloose on the shaft. The motor 28, through reduction gearing Within casing 38, drives shaft 'lil counterclockwise in Fig. 9, and shaft itil has chain and sprocket connection for driving shatt counter-clockwise. Shaft 13:2 has chain. and sprocket connection to pulley Sli for driving. it counterclockwise in Figs. 7 and. 9. Shaft llt. also has gear connection to. shaft lli for driving4 it clock- Wise at the same speed that shaft is driven counter-clockwise Shaft it has chain and sprocket connection to. shaft Slifer driving pulleys 3D and 32 clockwise in Figs. 'i and 9.

Ther :nain conveyor pulleys fit, t3., 5G in housing, Il at the left handl end of( table It all are mounted. on shaft 52 (Figs. Sand 8) andr all'A may be loose on. the shaft. Preferably the shaft will. be adjustably mounted on its support, as` at 511 in. Fig. 8, to permit adjustment ofhthe tension of conveyor belts` Ill, i6 and f8'.

Throughout their extents along the table, I9, the upper runs of the conveyor belts I'A', it', It are supported and guided in suitable tracks, such as the sheet metal tracksy as represented at It, Il' and' i9 in Figs. 3 and Il.

Circuitous pools of Work are provided at suit able locationsY along `the table it, and eachpool may have extent past any desired number of' Work stations. In l, the table Minas` three circuitous pools of work, one extending between the pair of rotatable disks 5G, 5t, anotherl eX- tending between the pair of rotatable disks tt; 62, and the third one extending betweenthej pair of rotatable disks G-i, t6. For convenience, the Work stations extending along the oppositesides of each circui'tousA pool of Work in Fig. l are nur-nbered to indicate that four work stations are-lm cated along each side of each circuitous pool. It should be understood, however, that ans7V-v desn sirednumber of! pools may be provided, andthat this individualisalesmen-WW110aa@as .desi-redt.

Work @aboutissant-alone there ls'rafmayfbeds'ede Referirnos-motelpartioularlvl-tozl'ies. 2 and. It.y thefill'ustratecl; relation 0fthei rotatable disk ltto the conveyor belts I4, I6, I8, andthestructureof 5t,AI are. repressentative.-n ot the relation. and struct, eroi-the otherfsiinarid-isksm GlLlZ, 641A and 6.6i. Diskitisrotatablyjsupported.in abeaningpiece 8F secured to -thequnderisidesfoi thebelt tracks I5', laf-therebeing an.opening 'Ill:tl-1roughv table; It for accommodating bearing piece BB. and thelpelependingl-shafht 51:; ot the disk.y Actually, however,A the disk rriayy rest by gravity on the,` two.

. oppositely `travelling;.conveyor belts M, I8so that the belts frictionallyengage and tend torotzaite:l theyrlislr..h In seinercases, the friction vbetween the. disk andv the .-travellingjbel-ts vmaag-,be4 relied upon for rotating-thedisk Hoyveversitwill vbe'` found -desirablein most casesl to positively drive the and asuitablysmall; frictional horse. power slow speed-` electric motor-is represented at 59 in E ig. 3, suspended from-bearing piece E8.` and directly coupled to the diskshaftV 5,1... This motor 59|and, thesimilarmotors for the other disks, may be ,connected-.A forv operationl Wheneverl the. conveyor beltsoperate,

asformed frongl` a ,single/piece of sheet; metal, with acentral raised platform partll' extending between tracks I5',V Ii9 and,supportingtheelevated central belt track I'L, as bestseen iti- Fig 4.v However,A it usually willv befound' moreconvenient to form the. tracks I5, I9and platform part Ilv three separate; pieces secured together by-l any-l conventional means.A The hub paltl ofthe disk ts under the platform part Il" Witlrslght extent through openings in theopposite side Wallswhich lead betweenthe tracks; I5 I9 and; the. platform I'Iz. Axed curved guide rail 'I2 extends around a. substantial` portion of, the periphery of disk forguiding Work boxes, or the like, as they are. being carried on the` disk from belt IB to belt I4. The mentioned openings in thev opposite side walls which exten-d between tracks I5 I9 and platform il arellarge enough. to permit passage ofthe Work boxes orotherunitsV ofv Work,l from one to the other' ot the. belts I4, I8'.; Also, the. platform part I-I which supports the central belt track I'I must be elevatedenough abovevthe disks to` permit thawork boxes, or; other unitsl of Work, t0: passA under platform. part Il' when being carried on` a disk fr.0m..one torv the,v other ofthe conve-yor belts I4, I8.

Inasmuch asl thee. structureand arrangement ,of disks 5S', 6.o, 62, Eiland 66. arev the. same as hasbeen4 describedy in connection with disk 56, no further detailed description of thedisksis considered y necessary.

Reverting to the showing: ofv Fig. 1 vvork` units which. are.v to proceed along the table IIl may be stacked. on the table at station I or la, and avvorker: places them in. successiononthe .central conveyor belt. i6.; Inclined tracks lll, 14a, lead from the central belt It.. respectively to the Work stations Z and. 2m, anda deilectorplate 'it is adjustably mounted at T and may beset for deflect-V ing the: work units onbelts ltto. eitherl one of the inclinedtracks; It or loaf., As represented, plate 'I6 is-.set todeect theivvork units toinclined track. 'I4 and the. units: deliver from the track tothe table. Itat station. 2; Afvzorker at station. 2 may inspect each uniti.of..Workeandp` if a unit meets; with appzuiival,,itiszplacedr on the lower conveyor belt-il torni. thaassemblylinais ,iust getti-neunte According to the invention, work units placed on conveyor belt I4 by the worker at station 2 travel circuitously past stations 2, 3, 4, 5, a, 4a, 3a, 2a until ejected from belt I4 at some one of these stations. The units travel to the right in Fig. 1 to the disk 58 which transfers them to belt I8 for travel to the left. When they reach disk 56, it transfers them back to belt I4.

A switch button 'I8 projects a little above the top of table I0 at a work-receiving location at each of the stations 3, 4, 5, 4a, 3a and 2a. Each of these buttons 18 is biased to closed position/but is adapted to be depressed to open position by the weight of a work unit resting on a button at workreceiving location. Fig. 2 shows work units in the form of rectangular boxes W and W resting on the buttons 'I8 at work stations 2a, 3 and 3a, and shows other boxes W and W' circulating between the disks 36, 38. Fig. 4 shows the box W depressing the button I8 to open position at station 3,

while the button 'I8 for station 2a, at the other side of table I0, is shown in its elevated closed position, the box W which is shown on this latter button in Fig. 2 being omitted in Fig. 4.

An ejector mechanism, indicated generally at 80, in Figs. 2 and 4, and shown in detail in Figs. and 16, is mounted opposite each switch button 18. Each ejector mechanism 80 may comprise a sheet metal plate 82 shaped as in Fig. 4 for fitting within the space provided under the platform I'I, between the conveyor belts I4, I8 and below the conveyor belt I6. A combined eccentric and cam 84 (Fig. 15) is rotatably mounted on the upper side of plate 82 and has pin-in-slot connection to one end of an actuating lever 86 which is pivoted at 88 on the plate. The other end of lever 86 has pin-in-slot connection to an ejector element 90 which is slidably mounted in guide 92 on plate 82. One end of ejector element 90 is equipped with the pusher foot 9|` for engaging a work box W or W when the ejector element 90 is operated toward its outermost position as shown in Figs. 2, 15 and 16.

The shaft 85 of the combined eccentric and cam 84 extends through plate 82 and is connected to a mechanism mounted at the under side of the plate and indicated generally at 94. Mechanism 94 may be a well known clockwork type mechanism which is adapted to rotate shaft 85 when its coil 95 is energized in response to closing of a switch button 'I8 provided that the ejector circuit is otherwise conditioned for an operation of the ejector. However, the ejector circuit will be so conditioned only if and when a work unit W or W is in a position bridging a pair of spring contacts in series with the particular switch button I8 which has closed.

Figs. 2 and l5 show two pairs of spring contacts 96, 98 and 96', 98 mounted on a supporting projection |00 which extends outward over the conveyor belts I4, I8. There will be one of these projections |00 at the approach to each Work station to which work is to be ejected from a circuitous pool. As best seen in Fig. 15, each pair of spring contacts 96, 98 and 96', 98' is mounted on a separate block so that one, two or more of the separate blocks may be mounted on a projection |00 to provide as many pairs of contacts 96, 98 and 96', 98 as may be desired at the approach to any particular work station. Each work unit W has a -metallic contact |02 thereon in position to bridge the pair of spring contacts 96, 98 on any one of the projections |00 as the work unit moves to a Contact bridging position opposite one of the switch buttons 18. Similarly, each work unit W' has a metallic contact |02' thereon in position to bridge the pair of contacts 96', 98 on any one of the projections |00 as the work unit moves into a contact bridging position opposite one of the switch buttons 18. As best seen in the wiring diagram of Fig. 19, each pair of spring contacts 98, 98 and 98', 90 at the approach to any particular work station is in series with the switch button 'I8 at that station in an ejector circuit for that station. Hence, before an ejector mechanism can operate to eject a work unit from a conveyor belt I4 or I8 to any particular work station, the switch button 'I8 at that station must be closed and also the spring contacts 96, 98 or 98', 98 at the approach to that station must be bridged by a work unit contact |02 or |02. When both of these conditions prevail, a circuit is closed to energize the step-up transformer |04 and the relay |05 of the aiected ejector mechanism 80. When the relay is energiaed, it closes the high side of the transformer through the motor which rotates the combined eccentric and cam 84. A holding switch |06 (Figs. 15 and 19) is closed by the cam as soon as the cam starts rotating thereby to maintain the transformer |84 energized until the cam makes a complete rotation, at which time the low portion of the cam permits the holding switch |08 to open. This single rotation of the combined eccentric and cam 84 will have effected a complete out and back cycle of movement of the ejector element 90, thereby to eject a work unit W or W from a conveyor belt I4 or I8 to a workreceiving location at one of the work stations. The arrival of the ejected work unit at a particular work station depresses the switch button 18 at that station thereby opening the ejector circuit.

Hence, assuming that a worker at station 2 is placing an adequate number of work units W or W on the lower conveyor belt I4, a circuitous pool of work between the disks 56, 58 will be available from which a unit of work will be ejected to any one of the stations 3, 4, 5, 4a, 3a, 2a as soon as a previously ejected unit of work has been removed from the work-receiving position at that station. If a worker at one of these stations is slower than the workers at the other stations, the latter workers receive work as fast as they can handle it, and the slower worker receives work only as fast as he or she can handle it.

When the assigned task has been performed on a work unit at one of the stations 3, 4, 5, 4a, 3a or 2a, the worker at that station places the unit on a central conveyor belt I6 from which it is delivered to station 6 by means of a deiiector plate I6 and inclined track 'I8 similar to the plate 'I6 and track 'I4 which deliver work units to station 2. The worker at station 6 inspects the work units and, if they are found satisfactory, places them back on central conveyor belt I6 for delivery to station 'I by means oi a deector plate I6 and track 'I8 as described in connection with "9 the delivery-of units to station 2. If desired, the deflector plates 'IS controlling delivery to stations 6 and 'I .may be set to deflect the units to tracks 14a, for delivery to stations 6a and a instead of to stations 6 and l.

The Worker at station places the units on the lower conveyor belt It to start or replenish the circuitous pool oi work between the rotating disks 6|), 62. Each of. stations 8, v9, Ill, 9a, 8d and Ia along this second pool has a switch button '|55 and ejector mechanism 80 associated therewith for supplying work to these stations as fast or as slow as individual workers can handle it, in the same manner described in connection with stations along the circuitous pool of work between the rotating disks 56, B.

Workers at stations along the second circuitous pool having completed their assigned task on work units W or W' place the units on the central conveyor belt I6 which carries them to the right, in Fig. l, until the leading work `unit on belt I Ei is stopped opposite vstations and Ha by a .ilXed transverse abutment :Ille which :has a switch `Contact IIi thereon adapted to be held closed when a work unit is 4stopped against abut-- `ment IBB. 'Switch contact IIS is in a circuit to a transfer mechanism indicated generally at l I2, which is adapted to transfer work units from the central belt I6 to the lower conveyor belt it thereby to automatically maintain the supply of Work units in the third `circuitous pool of work which operates between the rotating disks td, 65, at the right hand end 'portion of table Ic.

`Eachof stations l2, I3, |15, laand |211 along this third 4circuitous pool has a switch button -78 'and an ejector mechanism 8G associated therewith for supplying -work to these stations- `as fast or as slow as the individual workers can `-h-andleit, in the same manner described in connection with the stations along the first circui-tous pool operating between the rotating disks 56, 58. The workers along this third pool, having completed their assigned tasks on work units, place the units on central conveyor belt i6 for delivery -to the transverse vconveyor belt 2li, which, in turn, delivers them to the central conveyor belt 22 which travels to the left along table I2.

Three circuitous pools of work are illustrated in Fig. 1, along the table rI2 of `leg B of the disclosed assembly line apparatus, one .pool extend- VVVing between the rotatable vdisks IIA, IIB; an-

-other extending 'betiveenthe rotatable disks IIS,

. v| 21o; and the third Yone along table I 2, extending between the rotatable 'disks |22, IM. rIt should Abe understood, however, that the assembly line preferably will bie made `-up of separate :sections which may be variously moved and combined lto produce any desired number of work :stations and lany desired number of continuous circuitous pools, 4with suitable electrical plug-in electrical connections for the respective sections. Forexample, a section having rotatable :disks may `be substituted for a section not having disks, orvice versa, whereby the invention provides an eX- tremely flexible assembly line which .may be quickly adapted to `any particular conditions or requirements.

"In Fig. l, fthe stations .are numbered to 'indicate that there vare :six stations .along feach side :of 'the .circuitous pool which .operates `between :disks 5| llt, vI i6; .five .stations -alongeaeh side of thefcircuitous poolwhich operates between disks 'IftB, l2ii; i and :live stations valong :each side `of the 'eircuitousipool'which `opel-lates 'between disks I 22,

|24. These :numbers may be varied as may be desired.

The vconveyor ybelts 22, 24, 26 for table I2 may extend over pulleys at the opposite ends yof the table in the same manner as the conveyor belts I4, I6, I8 for table However, as shown in Figs. 1, l1 and 12, the drive for belts 22, 24, 25 is at the left hand end of the table I2 where a housing I3 encloses motor |26 which vdrives the two pulleys |28, |30 in unison counter-clockwise and drives pulley |32 clockwise, in generally the lsame manner that the pulleys SB, 32 and 34, at the right hand end of table i9, are driven.

Pulleys |34, |36, |38 at the right hand end of table I2 may be loosely mounted on shaft I4@ within the housing I3', with means |42 for adjust-ing .shaft ill@ to vary the tension on belts Figs. 7, 9, 11 and l2 show the transverse conveyor belt 2n extendingover a pulley IM in housing II and over Va pulley |46 in housi-ng I3', the pulley IM having chain and sprocket drive connection toa shaft |48 in housing II' which fhas gear connection to shaft 44. The transverse belt 2U extends vunder central conveyor belt |15 at table I il and over central conveyor belt 22 at table I2, and there is lguide means |51? for directing work units from the belt yI 6 to the belt 2U at table Hl, and guide means |52 for directing work units from belt 20 to belt 22 .at table I2.

Work units delivering from belt 20 to belt 22 are carried to the left until a unit is stopped `opposite stations I5, I5a by the fixed transverse abutment |54 which has the spring contact II!) thereon adapted to be held closed when la work unit is stopped against the abutment |54. Spring contact I lll is in a circuit to a transfer mechanism indicated generally at I I2, which is adapted to transfer work units from the central belt 22 to the lower conveyor belt 2t thereby automatically to replenish and maintain the supply of work units in the circuitous pool which `operates between `the vdisks I lil, H5. Each of stations It, Il, lil, IS, 2D, 19a, Ita, Ila and -Ia Aalong this circuitous pool has a Aswitch button 'i8 and an ejeetor'mechanism Sli associated therewith for supplying work from the pool to these stations as fast or as slow as the individual workers `'can `handle it, 'inthe lsame manner described in connection with the delivery of work from the pools lalong'table Ill, each worker, after vcompleting the assigned task on a work unit, placing it on central conveyor belt 22 `for advance to the left along tabley I2.

Work units 'moving to the left on conveyor 22 'from the stations along `the circuitous conveyor operating between disks IM, |16 are stopped by 'the fixed transverse 'abutment l 5B `with the leading work "unit opposite work stations 2|, 2id, and the abutment has aspring contact il thereon adapted to be held 'closed when a work unit is stopped against'the abutment les. The spring Contact Iiil is in a ycircuit to a transfer mechanism indicated generally at l |2, which is adapted to transfer work .units from the `central belt 22 to the lower conveyor v'belt 26 thereby to automatically replenish :and maintain the supply of work units in the circuitous pool which operates between the .disks H8, 12o. Each of stations 22, 23, "24, 3261.123@ and 24d along this latter circuitous pool rhasa switch button i8 and ejector ymechanism 82 .associated therewith for sup- Flying work from the pool to these stations iin the same r'nanner :discribed in :connection 4with the .circuitous pools. along 'table .l it, each worker,

11 after completing the assigned task on a work unit, placing the unit on central conveyor belt 22 for travel to the left toward the circuitous pool operating between the disks |22, |24.

Work units placed on central belt 22 at the stations 22, 23, 24, 25, 22a, 23a and 24a travel to the left until stopped by the fixed transverse abutment |58 with the leading work unit opposite work stations 26, 26a. Abutment |58 hasa spring contact thereon which is adapted to be held closed when a work unit is stopped against the abutment |58. Spring contact ||0 is in a circuit to a transfer mechanism indicated generally at H2, which is adapted to transfer work units from the central conveyor belt 22 to the lower conveyor belt 26 thereby automatically to replenish and maintain the supply of work units in the circuitous pool of work units operating between the disks |22, |24. Each of the'Y work stations 21, 28, 29, 30, 21a, 28a and 28a along this last one of the circuitous pools has a switch button 18 and an ejector mechanism 88 associated therewith for supplying work from the pool to these stations in the same manner described in connection with the pools of work along table |8, each worker, after completing the assigned task on a work unit, placing the unit on central conveyor belt 22 which carries it to the left hand end portion of table l2 where a worker at station 3| or 3| a may remove the units. An abutment |60 at Vthe extreme end of table |2 stops the units on belt 22 in positions for convenient removal.

All of the transfer mechanisms H2 for automatically maintaining the supply of work units in circuitous pools may be the same, and are shown as generally similar to the earlier described ejector mechanisms 80. However, the mechanism |2 for the circuitous pool at the right hand end portion of table I8 is arranged for transfer of work units from central belt I6 to the belt I8 which is travelling to the left along table l0, while each of the mechanisms ||2 for the circuitous pools along the table |2 is arranged for transfer of work units from central belt 22 to the belt 26 which is travelling to the right along table I2.

As best seen in Fig. 17, each mechanism 2 has a pusher element |68 slidably mounted in the guide |16 which is fixed on the bottom |12 of an enclosure whose side and top walls are removed in Fig. 17 A platform |14 is suitably supported in spaced parallel relation to bottom |12 (Fig. 18), and this platform has a clockwork mechanism |16 mounted on its upper side whose coil |11, when energized, effects rotation of a shaft |18 which extends through platform |14 and has a combined eccentric and cam |80 xed on its lower end at the under side of the platform. A step-up transformer |82 is controlled by relay |83 (Fig 19) whose coil is in series with the low side of the transformer. When the relay is energized, the high side of the transformer becomes connected to the coil |11 so that the shaft |18 rotates whenever the relay |83 is energized. An actuating lever |84 is pivotally mounted at |86 on bottom |12 and has pin-inslot connection at one end to the pusher element |68 and pin-in-slot connection at its other end to the combined eccentric and cam |80.L Pusher element |68 has a pusher foot |69 thereon for broadly engaging a work box or other unit during a cycle of operation of the transfer mechanism. A single rotation of thel combined eccentric and cam |88 effects a cycle of out and Vback.

movement of pusher element |68 for lateral transfer of a work unit which may be stopped against one of the abutments |08, |54, |56 or |58.

Fig. 17 illustrates that transfer mechanism ||2 which has abutment |54 associated with it, the spring contact on the abutment being in the circuit to the relay |83 and open excepting when a work unit W or W is stopped against abutment |54.

However, even though spring contact ||0 in Fig. 17 may be closed, the circuit to transformer |82 will not be energized unless there is a vacant space on lower conveyor belt 25 opposite the pusher foot |68 for reception of a work unit. A suitable number of normally closed spring contacts |88 are distributed along the path of travel of conveyor belt 26 in position to be pressed linward to open position whenever a work unit on belt 26 is passing one of the spring contacts |88. Three such springs contacts |88 are illustrated in Figs. 17 and 18, spaced apart slightly less than the length of a work unit W or W. Hence, unless belt 26 is free of any work unit throughout the extent of the distribution of the contacts |88, one or another of the contacts will be held open. The contacts |88 are in series with each other and with abutment contact H8 in the circuit to the relay |83.

Assuming that a work unit is stopped against abutment |54, holding its contact ||0 closed, and assuming that al1 three of the spring contacts |83 in Fig. 17 are closed, indicating an adequate vacant space on belt 26 for reception of a work unit, the relay |83 will be energized and the high side of transformer |82 will be connected for a rotation of the combined eccentric and cam |86 thereby to move the pusher element |58 transversely of belt travel for pushing the work unit at abutment |54 off belt 22 and over belt 26, as represented in Fig. 17. The initial rotation of combined eccentric and cam |86 closes the holding switch |98, as best seen in Fig. 19, thereby to maintain the relay and transformer energized throughout a complete rotation of the cam even though one of the spring contacts H0, |88 may open during the cycle of operation of the transfer mechanism.

Inasmuch as central belt 22 is elevated above the plane of belt 26, a tiltable plate |92 is pivotally mounted at i 84 in position to receive a work unit as it is pushed off the center belt 22. Plate |92 normally stands in a horizontal plane, elevated above belt 25 suciently to permit work units on the belt to pass under it without any interference. However, when a work unit is pushed onto plate |92 from center belt 22, the plate automatically tilts by gravity about its pivot thereby to bring an end portion of the work unit into engagement with the travelling belt 26 and the work unit is carried along on the belt, leaving the plate free to swing back to its horizontal position, ready to receive another unit.

Inasmuch as all of the transfer mechanisms ||2 are the same, and operate the same, the description of the one shown in Figs. 17, 18 is applicable to them all, and no further detailed description of the individual mechanisms 2 is considered necessary. The wiring diagram of Fig.- 19 shows the various transfer mechanisms ||2 in relation to the particular work stations predetermined group of Work stations, and the units of work in another pool circulating past work stations in another predetermined group of work stations, a straight-line conveyor for delivering units of work to a station past which one of said pools extends whereby a worker at `that station is supplied with units of work for `addition to the pool which is travelling past that station, ejector means at each of a plurality of said stations along each of said pools of circulating units of Work for ejecting individual units of Work from said pools to work-receiving positions at stations having said ejector means, and a switch button at each said work-receiving vposition responsive to removal of a unit of work pools to the location of a next succeeding pool.

- 2. A conveyor system for assembly lines and the like, comprising a support providing work stations arranged along the support, means for circulating a pool of units of Work past said work stations, a straight-line conveyor extending in relatively close general parallelism with the path of travel of units of work in said pool and adapted to convey units of work to said pool of circulating units of work, ejector means for transferring units of work from the straightline conveyor into said pool, an abutment for stopping a unit of work on the straight-line con veyor opposite said ejector means, means responsive to a unit of work stopped against said abutment for conditioning the transfer means for transferring said stopped unit of Work into said pool, and means responsive to work units on the circuitous conveyor for disabling the ejector means excepting when there is a vacant space on the circuitous conveyor into which a unit of work may be transferred.

3. A conveyor system for assembly lines and the like, comprising a support providing work stations arranged along opposite sides of the support, a pair of parallel. conveyor belts travelling in opposite directions along said support at locations generally centrally between the opposite sides oi the support, one of said belts travelling in one direction past the stations at one side of the support and the other of said belts travelling in theopposite direction past the stations at the opposite side of the support, a third conveyor belt located between and in a plane above said pair of belts and travelling in parallelism with the pair of belts in the same direction as one belt of the pair, a pair of rotatably mounted disks at substantially spaced apart locations along said support, said disks being located with their axes under said third conveyor belt and having radially extending disk portions overlying said pair of conveyor belts on opposite sides of said axes, there being means for eecting continuous rotation of said disks in the same direction when said belts are in motion, whereby said disks constitute means for carrying units of work from one to the other of said oppositely travelling belts of the pair thereby to cooperate with the pair of conveyor belts to circulate a pool of units of work past said work stations, means for ejecting a unit of work from said third conveyor belt to one of the belts of said pair thereby to maintain the supply of units of work in said pool, and means -v,disposed in the path of units of work circulating 16 in saidpool for disabling said ejecting means excepting when there is a vacant space in the pool for reception of a unit of Work ejected from said third conveyor belt.

4. A conveyor system for assembly lines and the like, comprising a support providing work stations arranged along opposite sides of the support, a pair of parallel conveyor belts travelling in opposite directions along said support at locations generally centrally `between the opposite sides of the support, one of said belts travelling in one direction past the stations at one side 0f the support and the other of said belts travelling in the opposite direction past the stations at the opposite side of the support, a third conveyor belt located between and in a plane above said pair of belts and travelling in parallelism with the pair of belts in the same direction as one belt of the pair, a pair of rotatably mounted disks at substantially spaced apart locations along said supp-ort, said disks being located with their axes under said third conveyor belt and having radially extending disk portions overlying said pair of conveyor belts on opposite sides of said axes, there being means for effecting continuous rotation of said disks in the same direction when said belts are in motion, whereby said disks constitute means for carrying units of Work from one to the other of said oppositely travelling belts of the 'pair thereby to cooperate with the pair of conveyor belts to circulate a pool of units of work past said rWork stations, means for pushing a unit of work from said third conveyor belt laterally toward one or said pair oi belts, a pivoted member in position to receive a said laterally pushed unit of work and adapted to tilt in respon-se to deposition of a unit of work thereon, said pivoted member normally bridging the path of travel of units of work in said pool and tilting in direction to deposit its unit of work on one belt of said pair thereby to add the said unit to said circulating pool of units, and means in the path of travel of units in said pool for disabling said pushing means when no vacant space is available in said pool for reception oi another unit of work.

5. A conveyor system for assembly lines and the like, comprising a support providing work stations arranged along the support, means providing a plurality of separate pools of circulating units of Work at different locations along said support, each pool of units of work extending past dierent ones or said stations along the support, a straight-line conveyor extending past the said plurality cf pools of circulating units of work and in relatively close parallelism with a portion of the path of travel of units of work in each pool, said straight-line conveyor being adapted to convey units to the location of one of said pools and to convey units of work from stations along said one pool to the location of the next succeeding pool, ejector means at one of said pools for transferring individual units oi work from the straightline conveyor into that pool, means in the path of travel of units in the latter said pool for conditioning the ejector means at that pool for a transferring operation only when a space is vacant in that pool for reception of another unit of work, ejector means at each of a plurality of work stations along each pool for ejecting units of Work from the adjacent pool to each of said plurality of stations along each pool, and means at a work-receiving position of each of said plu'- rality of stations along each pool for effecting an operation of theassociated ejector means only when the work-receiving position at any particular station is vacant.

6. A conveyor system for assembly lines and the like, comprising three parallel travelling conveyors of which two travel in opposite directions substantially in a common plane and the third conveyor is centrally disposed between the others and travels in a plane spaced above said common plane, means coacting with said oppositely travelling conveyors which are in the said common plane for conducting work units from one of said conveyors to the other` at one location therealong and for conducting work units from said other conveyor to said One conveyor at another location therealong, thereby to provide a circulating pool of work units between said conducting means, said centrally disposed conveyor being adapted to carry work units thereon for replenishing the supply of work units in said circulating pool of work units, means at spaced locations along said circulating pool of work units operative to eject a work unit from said pool at whichever one of said locations is in condition to receive a work unit, and transfer means operative only when there is a vacant space in said pool for transferring a work unit from said centrally disposed conveyor into said circulating pool of work units whenever a vacant space occurs in said pool due to ejection of a workgunit therefrom at one of said locations spaced along the circulating pool of work units.

7. In a conveyor system for assembly lines and the like having a travelling conveyor on which work units are carried, switch contacts at a predetermined location along the conveyor in position for at least one of them to be engaged by a work unit on the conveyor at said location, a normally closed switch at a receiving position adjacent to said location and to one side of said conveyor',` said switch being adapted to be held open when a work unit occupies said receiving position, yejector means adjacent to said location and t0 the other side of said conveyor, said ejector means being operative for ejecting a work unit from the conveyor, and means providing an electric circuit, in which said switch contacts and switch are connected in series, for effecting an ejecting operation of said ejector means only when a work unit on the conveyor closes the circuit through said switch contacts while said normally closed switch is closed due to absence of a work unit in said receiving position.

ISADORE GALPER.

References Cited in the file of this patent UNITED STATES PATENTS Number Name lDate 1,234,729 Champ July 31, 1917 1,710,969 Dempsey Apr. 30, 1929 1,906,339 Schrader May 2, 1933 2,303,755 Newton Dec. 1, 1942 FOREIGN PATENTS Number Country Date 118,841 Australia Aug. 31, 1944 

